Rather than clamping up dovetail joints on drawer boxes, you can pin the joints together with a small pin nail, which is easily hidden.

When I have a lot of dovetailed drawer boxes to assemble, I use my pin nailer instead of clamps for the glue-ups. I shoot a 1" headless pin through the top and bottom of each dovetailed corner. The tiny pins are barely noticeable, and they hold the joints securely until the glue sets. Works great for me.